Prosecutors urged jurors to recommend the death sentence for the gunman convicted of killing a judge and three others in an Atlanta courthouse shooting spree.
Brian Nichols in March 2005 was being taken to a courtroom when he beat a deputy guarding him, stole her gun and went on the rampage.
Prosecutor Kellie Hill told jurors Wednesday that the 36-year-old would try to again escape and kill if they sentenced him to life in prison.
The defense urged jurors to probe his background to determine whether execution is the right punishment. Nichols had pleaded not guilty by reason of insanity.
Instead, the same jury last week convicted him of 54 counts, including murder. The sentencing phase could last until Thanksgiving.
Nichols had already plotted to break out of jail, authorities said.